sibley (02/04/83)
In 4.1BSD, csh will not allow any "onintr" from a terminal. However, it is possible to get a login shell to ignore interrupts by sourcing a script with "onintr -" in it. If you later send an interrupt signal (^? or del) to this shell, there is no containing interactive shell to handle it, so it quits -- i.e., you get logged out and get a core dump of csh. I have (or rather, until I figured this out today, I had) an "onintr -" in my .login file. This was because it would put me in "mail" if I had mail, and I wanted to be able to send interrupts to mail rather than have them intercepted by the containing cshell. (And if you don't ignore interrupts, the shell does catch them rather than passing them to mail.) In retrospect, this was pretty dumb of me. Once interrupts are being ignored, it's pretty easy to send one to the login cshell. E.g., trying to kill a process which is in fact finished, although its output is still being sent to the teminal. Is this a bug or a feature? (I suppose by definition it's a feature...) Dave Sibley Department of Mathematics Penn State University psuvax!sibley